. Difficulty in obtaining and maintaining intravenous (i.v.) access for repeated administration of medications is a frequent complication encountered during chronic antibiotic therapy for life threatening infections. In a recent study, central venous access lines had to be discontinued in 45% of AIDS patients due to infections and other serious complications. Intraosseous (i.o.) administration, using the Osteoport is proposed as a safer alternative to intravenous administration.This research will evaluate i.o. administration of ceftazidime (CFTZ) through the Osteoport in an animal (goat) model. CFTZ has been chosen as representative of antibiotics which are commonly administered intravenously to AIDS patients. The pharmacokinetics of CFTZ will be compared between i.v. and i.o. administration. Plasma levels of CFTZ will be determined by HPLC on sequential blood samples obtained after administration of a single dose. After repeated i.o. administration of CFTZ, animals will be humanely sacrificed for tissue collection and histology to evaluate local pathology associated with i.o. administration.Demonstration of the suitability of this device and route of administration for CFTZ will direct the commercialization of the Osteoport to replace or supplement intravenous therapies in chronically ill patients. It is estimated that over 50,000 AIDS patients per year could benefit from this technology.